noun
relative humidity
Technical term used in meteorology, HVAC, and science. Refers to the amount of water vapor present in air expressed as a percentage of the amount needed for saturation at the same temperature.
今日の相対湿度は80パーセントです。
Today's relative humidity is 80 percent.
相対湿度が高いと、汗が蒸発し
When the relative humidity is high, sweat does not evaporate easily.